a. Field of the Invention
The invention relates to coated, shaped articles prepared from a biodegradable material and to processes for making and using such articles.
b. Description of Related Art
It has long been known that disposable articles are filling up the solid waste facilities of this country. Plastic articles, in particular, pose a difficult disposal problem. Such articles usually require many years to decay in landfills, and such articles may remain in essentially unaltered form for generations.
One potential solution for reducing the amount of plastic solid waste is recycling. A plastic product may, if properly recycled, have several "lives" in different forms and shapes. While recycling provides a useful and desirable means of reducing the amount of solid waste generated, it does not solve the problem of final disposal of the plastic.
In our society disposability has become a way of life. Sizable segments of the consuming public use products that are geared to convenience and these consumers are often not motivated to take part in the recycling projects that can significantly affect our solid waste landfills. With respect to consumer products, such as disposable razors, attempts at interesting users in marketing programs designed to facilitate recycling have met with failure. Consumers are apparently not eager to take the extra time or expend the extra effort to make such programs work. It is an object of the present invention to provide a shaped article, such as, but not limited to, a disposable razor, in a form that is acceptable to the disposable product using public while simultaneously offering an easy, efficient method for consumers to activate the degradation process.
Another potential solution to the problem of disposal of plastic solid wastes is to make plastic articles out of "biodegradable" materials. Generally speaking, biodegradable materials are those that can readily be broken down into constituent elements that are either beneficial to, or are at least not adverse to, the biosphere. An example of such a "biodegradable" plastic is NOVON brand biodegradable polymer, a starch-based polymer described in U.S. Pat. No. 4,673,438 and U.S. Pat. No. 4,738,724, which are incorporated herein by reference. Shaped articles made from such a material can rapidly be broken down in landfills and can even provide nutrients for the soil in the landfill in the process.
One difficulty with biodegradable plastics such as NOVON brand biodegradable polymer is that such materials are not well suited for use in wet environments. The very factors that make biodegradable plastics such as NOVON brand biodegradable polymer easily biodegradable make them susceptible to degradation in a wet environment. Disposable shaving razors, for example, are exposed to water daily in use and may be fully immersed. Such immersion would quickly lead to degradation of a disposable razor made exclusively from NOVON.
Accordingly, it is an object of the present invention to provide a shaped article, such as a disposable razor, substantially made from a biodegradable material such as NOVON, that is substantially biodegradable yet is suitable for use in a wet environment.